Pharmaceutical analysis

Pharmaceutical analysis is a standardized, scientifically validated testing process that evaluates a drug substance against predefined acceptance criteria. It anchors quality review in three separate results: identity, assay, and purity. Each result answers a different question, so you should not treat one value as a substitute for another when reading a laboratory report.

A complete pharmaceutical analysis requires separate testing parameters

A full assessment uses separate test parameters because no single method verifies every quality aspect. A report may show identity, assay, and purity side by side, but the results are not interchangeable: each uses its own measurement approach and supports a different conclusion.

• Identity confirms that the molecule matches the label claim. Laboratories typically use Mass Spectrometry (MS), which checks the molecule's exact mass against the expected compound.
• Assay determines the concentration or strength of the active substance and shows whether the product delivers the intended dose.
• Purity measures unwanted substances, such as synthesis byproducts, usually by High-Performance Liquid Chromatography (HPLC), which separates compounds for measurement.

Common misinterpretations of pharmaceutical lab reports

The main error is treating purity, assay, and identity as the same proof. An HPLC purity of 99% means only that 99% of the UV-detectable signal belongs to the main peak. It does not rule out contaminants UV detection may miss, such as residual salts or water.

A single HPLC peak also does not prove molecular identity; confirmation needs a separate method such as MS. Purity is not assay: purity concerns impurities, while assay concerns active dose strength. A lab report is data output, not a biological safety certificate or proof of suitability for human use. Reports from unregulated research labs may have less strict quality control and method validation than agencies like the FDA require, so their results may not reflect the true contents.

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